Oracle – Cannot TNSPING from VirtualBox Client to Database on Host

I am new to Oracle, attempting to learn about connecting remote clients to an Oracle 12c Database server instance.

SUMMARY: I cannot get TNSPING to work from a client machine to a known good database on a host machine.

DETAILS:

I am hosting the Oracle 12c database on my Windows 7 x64 development machine. I've done numerous tests of connecting to the database from that machine – TNSPING, SQL*Plus, ASP.Net web page, and they all connect to the database no problem. Great!

So I figured a next logical step is to try to connect from another client inside my network. I created a Win7 client using VirtualBox running on the same host (RM08) as the Oracle Database. I completely disabled Windows Firewall on that client machine. I then installed the Oracle Client on that virtual machine. That gives me SQL*Plus and various other tools, and led me through a configuration wizard to create a tnsnames.ora.

When I tnsping from that virtual/client machine to the Oracle host I get "ORA-12541: TNS: no listener". But I am confident the listener is in fact running, because the database works fine when I access from the host machine itself.

Further information:

— The host machine has IP address 192.168.1.6

— The virtual/client machine has IP address 10.0.2.15

— From the client machine I get success when I ping the host

— From the client machine I can successfully open up various ASP.Net web pages at http://192.168.1.6

— Windows firewall is completely disabled on BOTH the client and host machines.

On the client machine, the tnsnames.ora file has contents:

ORCL =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.6)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = orcl)
    )
  )

On the client machine, when I issue:

tnsping orcl

I get:

C:\Users\rmvirt>tnsping orcl

TNS Ping Utility for 64-bit Windows: Version 12.1.0.2.0 - Production on 20-APR-2
016 14:11:37

Copyright (c) 1997, 2014, Oracle.  All rights reserved.

Used parameter files:
C:\app\client\rmvirt\product\12.1.0\client_1\network\admin\sqlnet.ora


Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)
(HOST = 192.168.1.6)(PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = orcl)))
TNS-12541: TNS:no listener

If I ping by IP address, I get a similar message, but it mentions EZCONNECT, I assume because I including that option when installing Oracle client:

C:\Users\rmvirt>tnsping 192.168.1.6

TNS Ping Utility for 64-bit Windows: Version 12.1.0.2.0 - Production on 20-APR-2
016 14:13:26

Copyright (c) 1997, 2014, Oracle.  All rights reserved.

Used parameter files:
C:\app\client\rmvirt\product\12.1.0\client_1\network\admin\sqlnet.ora

Used EZCONNECT adapter to resolve the alias
Attempting to contact (DESCRIPTION=(CONNECT_DATA=(SERVICE_NAME=))(ADDRESS=(PROTO
COL=TCP)(HOST=192.168.1.6)(PORT=1521)))
TNS-12541: TNS:no listener

Finally, if I issue

tnsping badname, I get:

C:\Users\rmvirt>tnsping badname

TNS Ping Utility for 64-bit Windows: Version 12.1.0.2.0 - Production on 20-APR-2
016 14:15:15

Copyright (c) 1997, 2014, Oracle.  All rights reserved.

Used parameter files:
C:\app\client\rmvirt\product\12.1.0\client_1\network\admin\sqlnet.ora

TNS-03505: Failed to resolve name

That at least gives me confidence that my tnsnames.ora file is syntactically correct and being referenced.

I have read this somewhat similar question, with no luck: Using Oracle client to connect to remote database

I have also read the "Testing Connections" section from the "Database Net Services Administrators Guide" at Using Oracle client to connect to remote database.

But I am still stumped.

Can anyone suggest other troubleshooting steps?

Thanks!